My guess is that fat-soluble toxins that may occur in freshwater ecosystems would most affect apex species in these ecosystems. This is because fat-soluble toxins are stored in the fat reserves of animals, and then bioaccumulate up the food chain. So in this case, most of the toxin is not secreted, but stored within the food chain, and bioaccumulates, with the concentration becoming higher the further up the food chain.
Answer:
<h2>A polyadenylation signal or poly(A)
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Explanation:
Termination. In eukaryotes, transcription is terminated differently for the all 3 different RNA polymerases. Transcription is terminated by two elements: i) a poly(A) signal and ii) a downstream terminator sequence.
In eukaryotic protein-encoding genes, the cleavage site in the RNA occurs between an upstream( the sequence before the cleavage site) AAUAAA and a downstream GU-rich, separated by approx 40-60 nucleotides. After they both have been transcribed, a protein knows as CPSF and another protein called CstF( in humans) helps in termination.
A genetically modified organism (GMO) is any organism whose genetic material has been altered using genetic engineering techniques. The exact definition of a genetically modified organism and what constitutes genetic engineering varies, with the most common being an organism altered in a way that "does not occur naturally by mating and/or natural recombination". A wide variety of organisms have been genetically modified (GM), from animals to plants and microorganisms. Genes have been transferred within the same species, across species (creating transgenic organisms) and even across kingdoms. New genes can be introduced, or endogenous genes can be enhanced, altered or knocked out.
The correct answer is: prevent reception of a signal in a receiving neuron
Neurotransmitters are signal molecules or chemical messengers which transmit signals across a chemical synapse. Neurotransmitters send the signal, from one neuron (nerve cell) to another neuron, from neuron to muscle cell (motor plate), or from neuron to gland cell.
Drugs that bind to neurotransmitter’s receptor can have two effects on its action:
• Antagonists-they bind to receptor and thus prevent a neurotransmitter from binding to it
• Agonists-they bind to receptor and mimic the normal neurotransmitter (have the same effect as neurotransmitter).
Answer:
the penguins have a special care process since the hatching of the egg, the newborns receive care from their parents and have warmth from them placing themselves between their paws, the parents take turns caring for them and when the father is not with the chick, he goes in search of food, which he gives regurgitated, then the cris can go to a kindergarten where others of the same age are cared for by a herd of penguins, however his parents go to the sea and feed and continue to bring food to their son, this process it is kept until they change plumage and are ready to get their food on their own.
